diff --git a/src/cm95pbf/csp.py b/src/cm95pbf/csp.py
index 570fda3..0c8e70e 100644
--- a/src/cm95pbf/csp.py
+++ b/src/cm95pbf/csp.py
@@ -105,8 +105,12 @@ def resolve_depcnt02_instruction(
     if object_class == "DEPARE":
         drval1 = _float(attrs, "DRVAL1", 0.0)
         drval2 = _float(attrs, "DRVAL2", drval1)
-        if drval1 <= settings.safety_contour_m <= drval2:
-            safe = True
+        # Match OpenCPN DEPCNT02 control flow exactly: the chart's
+        # next-safe-contour fallback is only considered when DRVAL1 is
+        # already deeper than the mariner safety contour.
+        if drval1 <= settings.safety_contour_m:
+            if drval2 >= settings.safety_contour_m:
+                safe = True
         elif next_safe_contour_m is not None:
             safe = abs(drval1 - next_safe_contour_m) < 1e-4
     else:
@@ -605,9 +609,17 @@ def materialize_mariner_runtime_facts(
             out["depth_max_m"] = depth_max
 
     if name == "DEPCNT02":
-        contour = _optional_float(attrs.get("VALDCO"))
-        if contour is not None:
-            out["contour_depth_m"] = contour
+        if object_class == "DEPARE":
+            depth_min = _optional_float(attrs.get("DRVAL1"))
+            depth_max = _optional_float(attrs.get("DRVAL2"))
+            if depth_min is not None:
+                out["depth_min_m"] = depth_min
+            if depth_max is not None:
+                out["depth_max_m"] = depth_max
+        else:
+            contour = _optional_float(attrs.get("VALDCO"))
+            if contour is not None:
+                out["contour_depth_m"] = contour
 
     if name == "SOUNDG02" and sounding_depth_m is not None:
         out["s52_sounding_depth_m"] = float(sounding_depth_m)
diff --git a/web/s52_runtime_executor.js b/web/s52_runtime_executor.js
index 3427c40..aa378c7 100644
--- a/web/s52_runtime_executor.js
+++ b/web/s52_runtime_executor.js
@@ -81,7 +81,16 @@ function dynamicRules(procedure,props,settings,context){
     if(props.s52_source_object_class==="DRGARE"&&!Object.prototype.hasOwnProperty.call(props,"depth_min_m"))color="DEPMD";const out=[rule("AC",[color],{procedure:procedure})];if(props.s52_source_object_class==="DRGARE")out.push(rule("AP",["DRGARE01"]),rule("LS",["DASH","1","CHGRF"]));return out;
   }
   if(procedure==="DEPCNT02"){
-    const contour=numberValue(props,"contour_depth_m",0),safe=context.effectiveSafetyContourM!==null&&Math.abs(contour-context.effectiveSafetyContourM)<1e-4,q=numberValue(props,"s52_quapos_code",0);let out=[];
+    let safe=false;
+    if(String(props.s52_source_object_class||"")==="DEPARE"){
+      const d1=numberValue(props,"depth_min_m",0),d2=numberValue(props,"depth_max_m",d1);
+      if(d1<=settings.safetyContourM)safe=d2>=settings.safetyContourM;
+      else safe=context.effectiveSafetyContourM!==null&&Math.abs(d1-context.effectiveSafetyContourM)<1e-4;
+    }else{
+      const contour=numberValue(props,"contour_depth_m",0);
+      safe=Math.abs(contour-settings.safetyContourM)<1e-4||(context.effectiveSafetyContourM!==null&&Math.abs(contour-context.effectiveSafetyContourM)<1e-4);
+    }
+    const q=numberValue(props,"s52_quapos_code",0);let out=[];
     if(q>=2&&q<10)out=safe?storedRules(props,"s52_safe_dashed_rule_chain"):[rule("LS",["DASH","1","DEPCN"])];else if(q===0)out=safe?storedRules(props,"s52_safe_solid_rule_chain"):[rule("LS",["SOLD","1","DEPCN"])];
     if(safe){if(!out.length)out=[rule("LS",[q>=2?"DASH":"SOLD","2","DEPSC"])];out.unshift(sideEffect({display_category:"Displaybase",scamin:100000001}));}return out;
   }return [];